//---------------------------------------------------------------------------
//	Greenplum Database
//	Copyright (C) 2012 EMC Corp.
//
//	@filename:
//		CXformIntersectAll2LeftSemiJoin.h
//
//	@doc:
//		Class to transform of CLogicalIntersectAll into a left semi join
//---------------------------------------------------------------------------
#ifndef GPOPT_CXformIntersectAll2LeftSemiJoin_H
#define GPOPT_CXformIntersectAll2LeftSemiJoin_H

#include "gpos/base.h"
#include "gpopt/xforms/CXformExploration.h"

namespace gpopt
{
	using namespace gpos;

	//---------------------------------------------------------------------------
	//	@class:
	//		CXformIntersectAll2LeftSemiJoin
	//
	//	@doc:
	//		Class to transform of CLogicalIntersectAll into a left semi join
	//
	//---------------------------------------------------------------------------
	class CXformIntersectAll2LeftSemiJoin : public CXformExploration
	{

		private:

			// private copy ctor
			CXformIntersectAll2LeftSemiJoin(const CXformIntersectAll2LeftSemiJoin &);

		public:

			// ctor
			explicit
			CXformIntersectAll2LeftSemiJoin(CMemoryPool *mp);

			// dtor
			virtual
			~CXformIntersectAll2LeftSemiJoin()
			{}

			// ident accessors
			virtual
			EXformId Exfid() const
			{
				return ExfIntersectAll2LeftSemiJoin;
			}

			// return a string for xform name
			virtual
			const CHAR *SzId() const
			{
				return "CXformIntersectAll2LeftSemiJoin";
			}

			// compute xform promise for a given expression handle
			virtual
			EXformPromise Exfp
				(
				CExpressionHandle & // exprhdl
				)
				const
			{
				return CXform::ExfpHigh;
			}

			// actual transform
			void Transform
					(
					CXformContext *pxfctxt,
					CXformResult *pxfres,
					CExpression *pexpr
					)
			const;

	}; // class CXformIntersectAll2LeftSemiJoin

}

#endif // !GPOPT_CXformIntersectAll2LeftSemiJoin_H

// EOF
